Warp knitting machines are well known for use in the manufacture of knitted fabrics. For instance, a three-dimensional knit fabric may be knitted on a machine having two needle beds with multiple guide bars. Two warp knit fabrics are formed from pile yarns, stitch yarns and backing yarns, with the pile yarns (also referred to as the connecting yarns) connecting the two fabrics. After knitting, the fabrics are split into two pieces of fabric by cutting the connecting yarns. Each of the two resulting pieces of fabric has a flat knit surface on one side (the technical face) and a pile surface on the other side (the technical back), formed by the cut interconnecting yarns1. In some cases, the technical back is brushed to form a velvet surface, and the technical face remains unfinished. When such fabrics are used in garments, a lining is provided adjacent the technical face to avoid contact of the harsher technical face with the wearer's skin.
1This convention of “technical face” and “technical back” is employed throughout this patent application. It differs from the convention employed in U.S. Pat. No. 5,855,125. 
Warp knitting machines can also be used to manufacture double face knit fabrics having raised surfaces on both the technical face and the technical back. In the processes described, e.g., in U.S. Pat. No. 5,855,125, the entire disclosure of which is incorporated herein by reference, some of the cut connecting yarns (pile yarns) are pulled through the fabric, from the technical back to the technical face, by a napping process, and raised to provide a raised fleece surface on the technical back. Typically, about 20% to 70% of the pile yarn is pulled through the fabric to form the fleece. The amount of pile yarn pulled through can be controlled, e.g. by adjusting the pressure applied during napping and/or by adjusting the thickness of the stitch and/or backing yarns relative to the thickness of the pile yarns. Generally, the thinner the pile yarns are relative to the stitch and backing yarns, the less pile yarn that will be pulled through.